Sentences with phrase «ka b.p.»

The spike is dated to 71.1 ± 5 ka B.P. by layer counting (16) and more recently to 74.2 ± 1.7 ka B.P. by correlation to European speleothem records (17).

We conclude that the hypothesized «volcanic winter» that followed the Toba eruption did not have a significant impact on the climate of East Africa and was not the cause of a human bottleneck in Africa around 75 ka B.P.

Other features of the record are also redated, such as the East African megadroughts (24), which must have terminated at least 10 ka earlier than the previous estimate of 75 ka B.P. Clearly, existing comparisons of the Lake Malawi paleoclimate data to other regional and global records (24, 25, 32) will need to be revised in the light of these findings.

Here we take the age of 75.0 ± 0.9 ka B.P., which was calculated using the currently best constrained 40Ar / 39Ar optimization model (4, 31) as the most robust age for the YTT, and import it into a revised Bayesian age model for the Lake Malawi central basin core, MAL05 - 1C (Fig. 4).

A revised Bayesian age - depth model for the upper 30 m of MAL05 - 1C based on 15 radiocarbon dates (24) and the age of the YTT: 75 ± 0.9 ka B.P. (4).